ORGANOCHLORINE AND PYRETHROID PESTICIDES ANALYSIS IN DAIRY MILK SAMPLES COLLECTED FROM COTTON GROWING BELT OF PUNJAB, PAKISTAN

The present study work was aimed at to monitor the residue level of some selected pesticides (Dichloro diphenyl tricthloro ethane, Dichloro diphenyl dichloro ethylene, endosulfan, aldrin, cypermethrin, deltamethrin, permethrin, and bifenthrin) in milk samples collected from the cotton growing belt of the Punjab province. The residue level of these pesticides in dairy milk samples was analyzed on High Performance Liquid Chromatography (HPLC) system. About 70% of the collected samples were found contaminated with either of the analyzed pesticides. Aldrine was detected in 35% samples with mean concentration level of 0.68 μg/ml, ranged between 0.32 μg/ml and 5.19 μg/ml. However, DDT, DDE, and endosulfan prevailed comparatively in lower percentage such as 10%, 9%, and 7%, respectively. DDT ranges between .003 μg/ml and 0.40 μg/ml, with mean concentration level of 0.01 μg/ml. Whereas DDE is present with mean residue level of 0.04 μg/ml, ranging from 0.15 μg/ml to 1.23 μg/ml. Lower level of DDT residues in milk indicates that the further application of DDT has been ceased which is also reported by other monitory studies conducted in most of the countries. Mean concentration level of the Endosulfan in milk was 0.13 μg/ml. Among pyrethroids pesticides detected in milk samples, bifentrhin was present with the highest mean concentration level of 1.68 μg/ml followed by permethrin with mean residue level of 1.24 μg/m. The mean residue level of cypermethrin and deltamethrin was 0.23 μg/ml and 0.21-g/ml respectively. The results also indicated that 23%, 21%, 18% and 7% of the milk samples were contaminated with cypermethrin, bifenthrin, permethrin and detlamethrin, respectively.